Apparatus for the placing of thin wall well screen pipe or tubing horizon-tally into a subterranean formation



Apnl 13, 1965 s. G. ALLEN ETAL 3,177,955

. APPARATUS FOR THE PLACING OF THIN WALL WELL SCREEN PIPE OR TUBING HORIZONTALLY INTO A SUBTERRANEAN FORMATION Filed June 11, 1962 3 Sheets-Sheet l INVENTORS. ROBERT E. RE/MUND Y STERLING G. ALLEN B MAHO EY. MILLER QRAf IBO ATTORNEYS.

p 13, 1955 s. e. ALLEN ETAL 3,

APPARATUS FOR THE PLACING 0F THIN WALL WELL SCREEN PIPE 0R TUBING HORIZONTALLY INTO A SUBTERRANEAN FORMATION Filed June 11, 1962 5 Sheets-Sheet 2 "@Muv INVENTORS. 35

ROBERT E. REIMUND 5 BY STERLING G. ALLEN 3 E 5 MAHONEY,MI: fR&RA 0 Y5. A]

TOR E Aplll 13, 1965 5 ALLEN ETAL 3,177,955

APPARATUS FOR THE PLACING OF THIN WALL WELL SCREEN PIPE OR TUBING HORIZONTALLY INTO A SUBTERRANEAN FORMATION 3 Sheets-Sheet 3 Filed June 11, 1962 5 ROBERT E. REIMUND BY STERLING cs. ALLEN MAHONEY.MI LER a. R Ba BY TTO NEYS.

United States, Patent 3,177,955 APPARATUS 1 03 THE PLAClNG @F THIN WALL WELL SCREEN FEE 0R TUBING HQREIZGN- Ohio Filed June 11, 1962, Ser. No. 201,530 6 Claims. (til. 175-21) Our invention relates to apparatus for the placing of thin wall well screen pipe or tubing horizontally into a subterranean formation. It has to do, more specifically, with apparatus for installing thin wall screen pipe, tubing or casing by pulling it rather than pushing it into a subterranean stratum or formation, such as a water-bearing stratum, for the purpose of collecting water therefrom. However, our invention is not necessarily limited in its purpose to the collecting of water.

The usual method of installing well screen pipes or the like'is to force them horizontally outwardly from a central vertical shaft or caisson. This is usually accomplished by means of hydraulic jacks located in the caisson which push the screen pipe outwardly. lacking pressures ranging from 50-100 tons on 6 or 8 inch screens and as much as 400 tons on 24 screens require that the screens be fabricated with heavy steel walls to provide sufficient strength to resist jacking pressures. Efiicient water-intake louvers or openings with a high percentage of open area, such as those used in standard thin wall screens, cannot be provided in the heavy walled screens previously required.

To overcome this disadvantage, prior art methods have projected from the caisson a heavy wall outer pipe, placed a thin wall screen inside the outer pipe and then retracted the outer pipe. The time and expense of removing the outer pipe is as great as the initial projection therefore rendering this method impractical.

Difficulty with prior art methods of installing screens has also been encountered in sealing the caisson port through which the screen is projected. In extremely deep installations, exterior pressures in the port seal, developed by hydrostatic heads of fluid in the stratum, may be as great as 100 p.s.i. or more and it is obvious that it is diflicult to provide a seal which would satisfactorily resist this pressure. Prior art seals have relied upon compressed packings to resist this pressure but the seals have not been adequate. Prior cone-shaped seals extending into the caisson port from the inner surface of the caisson permitted efiicient outward movement of tubing or screens but retarded or completely prevented the retracting of such screens, since the outer lip of the cone seal or stuffing box ring would'be caught by the rough exterior of the screen and rolled inwardly thereby locking the seal against the pipe or screen and completely preventing the screen from being retracted without removing the cone sea]. In the event of a high hydrostatic pressure and large resultant quantity of water existing in the surrounding formation, removal of this cone seal is often extremely difiicult or even impossible thereby preventing the retracti-on of these outer pipes or screens.

Prior art methods usually employ pointed conical heads, used as forward driving members on horizontal tubes or screens. These have continuously caused tube or screen lines to climb upward while they were being jacked in a forward direction. The reason for this is obviously the fact that all the materials from the stratum are not removed from the area between the point of the conical head and the elevation of the bottom of the screen. Therefore, the conical point slides upward on these unremoved materials causing the head and following screen to climb upward as each succeeding section 3,177,955 Patented Apr. 13, 1955 "ice is jacked outward. Complete removal of these materials is seldom effected since the holes or material removal ports usually provided in the conical head cannot be placed as low as the bottom of the screen and therefore the downward flow of water from the formation enters into the upper ports in the head and cannot wash material into the head at an elevation lower than the bottom ports of the conical head which are never as low as the bottom of the pipe. 7

Prior methods have been used wherein it is claimed that by selectively cleaning the interior of the screen, sagging of the screen is prevented and this prevents theconical head from traveling upward. However, in actual practice, this selective cleaning has not been successful in preventing the upward climb of the head and screen.

According to our invention, We employ a heavy jacking dowel or pipe, usually in the form of a heavy steel pipe, for taking the jacking thrust or pressure rather than applying it to the screen pipe. A driving head is mounted on the forward end of the dowel and this head is pushed forwardly into the stratum by the jacking dowel. The screen pipe surrounds the jacking dowel and is suitably connected to the head so that as the dowel pushes the head, the head pulls the screen pipe. Since the screen pipe is pulled, only tension forces, rather than compression forces, are applied thereto and, consequently, the screen pipe can be of much lighter weight or thinner construction. Therefore, it is economically feasible to make the screen pipe of non-corrosive material such as aluminum, copper, bronze, etc.

The jacking dowel is preferably constructed of steel with a hollow center and shall have sufficient strength to withstand all jacking pressures. ,It is fabricated with threaded joints or suitable connections as is the screen pipe. Dowel sections are in lengths equal to the outer screen lengths. The forward dowel section may have a slip male fitting to engage a female head assembly or may have a threaded end to screw into the forward head assembly that will permit retracting the complete assembly for realignment.

Our method may be used with either an open end cutting shoe on the head assembly or with a closed headassembly or with jet or other type heads.

Relief ports are placed in the dowel throughout its entire length for permittingfine soil materials, which might tend to collect between the dowel and the outer screen, to pass through the ports into the dowel and be carried by the water from the surrounding formation through the dowel and into the caisson for removal. This removal of fine materials from the space between the dowel and the outer screen will prevent a friction lock between the dowel and outer screen and permit removal of the dowel after final positioning of the screen.

A double flanged rubber or resilient packer is provided between a port casting and the outer well screen and is so designed as to permit the screen either to be jacked forward or to be retracted in a rearward direction while continuing to provide an effective seal for either direction of screen travel with no adverse binding effect.

Because of extreme hydrostatic exterior pressures around the caisson port, we provide for pressurizing and expanding this seal with a pneumatic or hydraulic medium which permits the seal to be expanded against the screen with sufficient pressure to overcome the outer force brought to bear on the seal by hydrostatic pressure developed in the surrounding formation. The pneumatic or hydraulic pressure for expanding the seal will further provide a better seal on rough or offset exterior screen surfaces such as screen ofiset couplings or offset louvers or openings in the screen wall which are necessary to eificiently screen fine gravels and provide the greatest amount of open inlet area.

We provide a head so designed as to provide material removal ports at the same elevation as the bottom of the screen thereby providing complete removal of material at the bottom of the screen. This head construction further eliminates the incline provided by the bottom of the pointed conical head thereby preventing any upward thrust against the head and eliminating all upward chrnb of the head. The distance on the previously used pointed conical head between the point and the bottom of the screen would be as much as 4 inches on an 8-inch diameter screen and as much as 12 inches on a 24-inch diameter screen. It can be readily seen that with this prior art head, stratum materials being washed into the conical head by the natural downward flow from the formation could not possibly remove materials at the bottom screen. elevation.

The return material line in previous use has been attached at the center of the inward end of the conical head. This tends to cause an accumulation of material in the bottom of the head due to the velocities of incoming water not being sufficient to raise these materials to the elevation of the material line for removal. We attach the material line in the lower section of the head to prevent this accumulation and give consequent better material removal outside of the lower head section.

According to our invention, seals composed of rubber or other resilient material are placed at intervals of several inches, as required, to prevent an excessive flow of water into the inner chamber as the dowel'is retracted and removed after final positioning of the screen. These seals have a diameter slightly greater than the inside diameter of the screen to provide an effective seal. They are attached to the dowel sections by wire wrapping or bolted metal hands. They are of sufficient sequence to assure that one seal shall always be positioned within the outer port seal, located in the caisson wall, as the dowel is being retracted.

The accompanying drawings illustrate our apparatus for installing a thin well casing'orwell screen by pulling it into a subterranean formation.

In these drawings:

FIGURE 1 is an axial vertical sectional view illustrating a vertical caisson with a lateral screen pipe being extended horizontally therefrom, the screen pipe being installed by using our apparatus.

FIGURE la is a horizontal sectional view taken on line I a-1a of FIGURE 1 showing jack positions for forcing the dowel outward. 7

FIGURE 2 is an enlarged axialror fragmentary elevational sectional view taken at the position indicated at line 2-2 of FIGURE 1 showing the caisson port expansion seal of the apparatus of our invention.

FIGURE 3 is an enlarged fragmentary axial or elevational sectional view taken at line 3-3 of FIGURE 1 illustrating the screen pipe and the associated installing pulling mandrel or dowel and wash or material return line together with the sealing means used therebetween.

FIGURE 4 is a transverse vertical sectional view taken along line 4-4 of FIGURE 3.

FIGURE 5 is an enlarged fragmentary axial or vertical sectional view taken along line 5-5 of FIGURE 1 and illustrating the pulling head assembly at the leading ends of the screen pipe and pulling mandrel or dowel and the associated wash or material return line together with the sealing means therebetween. 7

FIGURE 6 is a transverse vertical sectional view taken along line 6-6 of FIGURE 5.

FIGURE 7 is a fragmentary top plan View taken along line 7-7 of FIGURE 5 showing the pulling head.

FIGURE 8 is a view similar to FIGURE 5 illustrating a different arrangement of pulling head and mandrel or dowel.

FIGURE 9 is a transverse vertical sectional view taken along line 9-9 of FIGURE 8. V With reference to the drawings, in FIGURE 1 we have illustrated schematically one water collecting installation embodying our invention. A vertical caisson or shaft 15 is sunk into the earth so that its lower end is adjacent a watenbearing formation. This casing 15 may be sunk in the usual manner and is substantially water-tight. At a suitable level, one or more ports 16 are provided in its wall and intake well screens or pipe 20 is adapted to be projected horizontally outwardly through the port 16 into the water-bearing formation.

The water which collects in the caisson after installation of the screen 20 is removed by means of a suction line 18 extending from the lower portion of the caisson upwardly to a pump 19 at the surface.

The well screen 24 is preferably in the form of thinwall tubing which is provided with a suitable pattern of apertures of suitable outline. The screen or perforated pipe may be of very light material, because of the manner in which it is extended by our method, and, therefore, it will be economical to form it of corrosion resisting material such as copper, bronze, aluminum or stainless steel. The extension of the screen pipe and associated structure is accomplished by means of a suitable jacking unit 17 disposed in the caisson 15. The pipe or screen Zt'l and associated pipes will be composed of relatively short lengths or sections of lesser extent than the diameter of the caisson 15 so that they may be successively coupled together as the screen pipe is projected horizontally outwardly from the casing and through the port 16.

The forward or leading section of the screen 20 is pro-' result is a nose which has a straight but transversely curved supporting surface with a convex relatively pointed leading surface that converges upwardly and inwardly and also upwardly and rearwardly. As will later appear, this facilitates pushing of the nose through the subterranean formation. The nose 26 is of circular cross-section at its rear edge and this edge is secured, such as by welding, to the forward edge of a heavy pipe section or V sleeve 29 which also may be of steel. The forward edge of the leading screen section is permanently secured to the rear edge of the sleeve 29. in any suitable manner such as by welding. Positioned in the forward end of the sleeve 29 in engagement with the rear edge of the nose portion 26 is a thrust-transmitting collar 30, this collar fitting snugly within the sleeve29 which is of less wall thickness than the adjacent edge of the nose portion 26,

thereby providing the thrust shoulder 31 on the inner edge of the nose portion.

The collar 39 is provided with a rearwardly opening annular socket or groove 32 for receiving the forward circular end of a jacking dowel 35 which may be in the form of a heavy steel pipe. The. socket at its open end is provided with an outward flare 33 which will aid in centering the edge of the dowel 35 relative to the socket. This dowel, like the screen 20, will be made of short sections, which correspond in length to the screen pipe sectionsrand which are suitably coupled together. The forward edge of the jacking dowel 35 will slip loosely into the annular groove or socket 32 and it can be pulled inwardly therefrom whenever desirable.

The jacking dowel or pipe 35 is of less diameter than the sleeve 29 which connects the nose 26 and the screen 20. Therefore, the sleeve 29 is provided internally with a series of angularly spaced jacking dowel guide lugs 36 (FIGURES 5 and 6) each of which has a tapered camming rear edge surface 37 and which is suitably fixed in the sleeve 29 inwardly of the collar 30. Thus, the lugs 36 ,will tend to center the leading edge of the jacking ii dowel relative to. the socket 32 as it is slippedinto the head assembly 25.

The nose 26 is provided with a suitable number of apertures 33 at its forward side which extend in a pattern upwardly and rearwardly from the bottom wall 27. The hollow chamber 39 formed within the nose is provided with an outlet adjacent its fiat lower wall 27 which eX- tends through the collar 39 and receives the forward end of a tube 41 (FIGURES and 6) that is fixed therein. This tube extends angularly rearwardly and with a slip fit into a central opening in a collar or ring 42 which is fixed within the dowel pipe 35. The tube 41 extends through the collar 42 and is coupled by a flush-type screw joint or coupling 4-3 to the forward edge of the leading section of the material return or wash line or pipe 4-9. This pipe like the members 35 and 2% will be of short sections or lengths that can be coupled together, all the joints of this line being of the flush type (FIGURE 3). The sections of the dowel 35 may bejoined together by a suitable joint as by screw collars 44 receiving the adjacent threaded ends of the pipe sections. Similarly, the sections of the screen 29 may be joined by threaded collars 45.

Thus, the outer screen pipe 29, the smaller diameter dowel pipe 35, and the still smaller wash pipe 42 are concentrically disposed to provide an outer annular space 46 between the members 29 and 35 (FIGURES 3 and 4) and an inner annular space 47 between the members 35 and 40. At suitable axially spaced positions in this space 46, combination water stops and jacking dowel guide rings 50 (FIGURE 3) are arranged in pairs. Each ring is of resilient material, preferably of rubber or plastic, and is attached to the outer surface of the dowel pipe 35 so that it yieldingly engages the inner surface of the screen pipe 2%). Throughout its length, the jacking dowel pipe 35 is provided with ports 51 for allowing fines, which enter the space 4-6 through the screen pipe 20, to be removed into 'the'pipe 35 to prevent friction lock around the screen pipe.

As previously indicated, it is necessary to have sealing means at the port 16 to prevent a rush of water into the caisson as the screen pipe 2! is being projected therefrom. It will be noted that the screen pipe is projected through a port sleeve 53 which may be fixed in the concrete wall of the casing as it is formed or it may be cemented in place after forming. The sleeve 53 is of substantially greater diameter than the screen pipe as shown in FIGURE 2. Secured to the inner end of this sleeve is a port gate valve 54 which may be closed manually after the screen pipe has been projected. The sealing rings 5% will prevent flow of Water from the annular space 46 into the caisson. To prevent flow from the annular space 47 into the caisson, the pipe 49 has a packer unit'55 (FIGURES 2 and 3) associated therewith at the port 16. This unit 55 comprises a flexible sleeve 56, such as rubber, slidably mounted on the pipe 49 and carrying a plurality of integral axially spaced sealing rings 57. These rings 57 are similar to the rings 52) and fiex outwardly into engagement with the inner surface of the jacking dowel 35. The sleeve 56 may be caused to snugly engage the pipe 49 by adjustment of the tensioning rods 59 extending therethrough which cause the inner shoulders 55:: to engage the pipe. The packer is held in line 58 attached to the sleeve 56 and extending into the caisson, it being understood that it will be threaded through successively added sections of the screen pipe and its inner end will be suitably held during screen projection.

An expaansion seal 65 is provided around the screen 20 at the port 16 to prevent inward rush of water during screen projection between the port sleeve 53 and the screen pipe 29. This seal 6% includes the inner and outer rings 61 and 62 which snugly receive the screen as it is projected therethrough, these rings being clamped by bolts 63 to the inner and outer ends, respectively, of the sleeve 53; It will be noted that the gate valve 54 may be secured to the ring 61 by the bolts 66. Between these rings and the associated ends of the sleeve 53 are clamped the peripheral flanges 64 of an expansible sleeve 65 which may be of rubber or other suitable flexible material. Pressure fluid, such as hydraulic fluid or air, may be supplied within the chamber 67 provided by the seal 65 by means of a tube 68 for expanding it to tightly engage the outer surface of the screen 20.

With the apparatus so far described, the following steps should be followed to project the screen pipe 20:

(1) Insert the .forward section of jacking dowel 35 into position in the head assembly 25.

(2) Slip first section of screen or tubing 20 into POSi? tion over the hollow jacking dowel and over the welding shoulder at the inner end of the head sleeve 29. Weld screen or tubing permanently to the head assembly.

(3) Screw first section of return material line 40 into the rear end of the tube section 41 of the head assembly.

(4) Place material return line seal 55 over return line and move line to forward position. Insert assembled unit (head, jacking dowel, screen and material return line) horizontally through port 16 and seal in the caisson wall with rear portion of unit resting in jack frame cradle of jack unit 17 that has been positioned on floor of caisson and in line with port.

(5) Expand the seal 65 around the section of screen pipe 20 inserted through the port '16.

(6) Apply hydraulic jacking pressureto rear of jacking dowel 35 and project head through outer port plug and in.- to the soil formation. Continue applying pressure to the jacking dowel until the head has pulled the first section of screen or tubing to within one foot of the port flange.

(7) Return jack cradle to original starting position. Insert second section of pusher dowel 35 into second section of screen or tubing 20 and insert return material return line 40 into jacking dowel. Thread return line 4%] into first section of return line, thread second section of jacking dowel 35 into first section of jacking dowel and attach second section of screen or tubing 20 to first section by welding or by threaded coupling. Repeat jacking operation, projecting the head assembly and pulling the screen or tubing 20 into the formation. Repeat the Whole process until the screen or tubing 20 has been pulled horizontally to the desired length in the formation.

(8) After horizontal lateral has been pulled to its desired length the return material line 40 is' unscrewed from the head assembly and removed through the return line seal to the caisson. The interior of the hollow jacking dowel and the area 46 between the dowel and the outer screen or tubing 20 is flushed free of soil materials.

(9) The annular space 4-6 between the jacking dowel 35 and the outer screen or tubing 2% is flushed free of material to prevent friction lock of the jacking dowel during removal. The natural static head of water in the formation or compressed air may be used to flush materials from this annular space through the cleaning ports 51 provided in the jacking dowel wall 35 and into the caisson 15. The jacking dowel is then pulled from the screen or tubing through the port into the caisson.

In FIGURES 8 and 9, we have illustrated a modification of our apparatus. In this instance the jacking dowel 35a serves a dual purpose, that is, to pull the screen pipe outwardly and to return the removed fines or other material inwardly. In this instance the return line is not used at all. In' this instance a packer similar to the packer will be used but instead of the sleeve 56, a solid plug or closed sleeve will be used.

It will be apparent from the above description that we provide apparatus for installing a water-collecting screen when the screen is pulled into the water-bearing formation rather than pushed. Therefore, the screen may be of thin corrosion-resistant material. The screen pipe is projected by meansof an inner relatively heavy jacking 7 pulling dowel which can be removed with ease after the screen projection is accomplished. The head assembly is of novel form and the nose is so shaped that it will not tend to ride upwardly as it is projected. This is due to the fact that the bottom surface of the nose is straight or horizontal in a longitudinal direction and the, material entrance openings extend completely to the bottom. The caisson is sealed at the port during projection of the screen pipe by the pressure-actuated seal around the screen pipe and the flexible seals between the screen pipe and the jacking dowel as Well as between the jacking dowel and material return line when one is used.

It will be apparent from the above that our apparatus is novel and has many advantages. Some of these advantages have been discussed and others will be apparent.

Having thus described our invention, what we claim is:

1. Apparatus for placing a tube laterally into a subterranean formation from a suitable shaft extending thereinto which comprises a driving head, a tube connected to the head so that it will be pulled thereby, and a pushing dowel Within the tube and removably engaging means on said head so as to push it outwardly when the dowel is forced outwardly, said driving head comprising a nose portion having a laterally and upwardly diverging surface with material-passage openings extending therethrough and a longitudinally straight but transversely curved lower surface.

2.. Apparatus according to claim 1 in which said openings extend all the way to the lower surface, and a material return line portion extending upwardly and inwardly from said nose in said head and connected to a material return line extending outwardly through said dowel, a transverse imperforate wall in said nose portion adapted to provide a chamber in said nose portion with which said material-passage openings communicate, said wall having the material return line portion mounted therein and communicating with said chamber.

3. Apparatus for projecting a tube into a subterranean formation which comprises. a driving head, a perforated tube connected to the head so that it will be pulled thereby and a pushing dowel within the tube and removably engaging means on the head so as to push it when'the dowel is projected, said dowel being of hollow tubular form and being disposed relative to the tube to provide a space therebetween, and having openings in the wall ea thereof leading from said space into the interior of the dowel, and sealing rings longitudinally spaced along the dowel in said space between the dowel and the tube, said rings being carried by the outer surface of the dowel and yieldably engaging the inner surface of the tube.

4. Apparatus according to claim 3 including a packer for sealing the inner end of the dowel, said packer comprising a member disposed within the dowel and yieldingly engaging the inner surface of the dowel.

5. Apparatus according to claim 4 wherein the dowel has a material return line centered therein, said packer surrounding thereturn line and yieldingly engaging both the inner surface of the dowel and the outer surface of the return line, said driving head having a material-receiving chamber at its leading end having inlet material-passage openings leading thereinto, said chamber including a rear transverse imperforate wall in which the leading end of the material return line is mounted in communication with said chamber.

6.. A driving head for placing a thin Wall tube in a subterranean formation comprising a nose portion having a material-engaging forward surface with openings formed therein which communicate with a chamber within the nose portion, said surface curving upwardly and laterally, a thrust collar at the rear of said nose portion and rigidly connected thereto, said collar having a socket for receiving the forward end of a pushing dowel, said collar being adapted to receive the thin Wall tube in surrounding relationship and which is adapted to be secured thereto, said nose having a lower supporting surface which is straight longitudinally but which curves transversely.

References Cited by the Examiner UNITED STATES PATENTS 1,993,365 3/35 Englebright -62 2,383,496 8/45 Nebolsine 175-62 2,622,683 12/52 Silitch et a1. 16650 X 2,708,000 5/55 Zandmer 166--100 2,904,113 9/59 McMahan 166100 FOREIGN PATENTS 717,229 10/54 Great Britain.

CHARLESE. OCONNELL, Primary Examiner. BENJAMIN BENDE'IT, Examiner. 

3. APPARATUS FOR PROJECTING A TUBE INTO A SUBTERRANEAN FORMATION WHICH COMPRISES A DRIVING HEAD, A PERFORATED TUBE CONNECTED TO THE HEAD SO THAT IT WILL BE PULLED THEREBY AND A PUSHING DOWEL WITHIN THE TUBE AND REMOVABLY ENGAGING MEANS ON THE HEAD SO AS TO PUSH IT WHEN THE DOWEL IS PROJECTED, SAID DOWEL BEING OF HOLLOW TUBULAR FORM AND BEING DISPOSED RELATIVE TO THE TUBE TO PROVIDE A SPACE THEREBETWEEN, AND HAVING OPENINGS IN THE WALL THEREOF LEADING FROM SAID SPACE INTO THE INTERIOR OF THE DOWEL, AND SEALING RINGS LONGITUDINALLY SPACED ALONG THE DOWEL IN SAID SPACE BETWEEN THE DOWL AND THE TUBE, SAID RINGS BEING CARRIED BY THE OUTER SURFACE OF THE DOWEL AND YIELDABLY ENGAGING THE INNER SURFACE OF THE TUBE. 